ERC FUNDED PROJECTS

ProjectFrom herds to empire: Biomolecular and zooarchaeological investigations of mobile pastoralism in the ancient Eurasian steppe

Host Institution (HI)CHRISTIAN-ALBRECHTS-UNIVERSITAET ZU KIEL

Call DetailsConsolidator Grant (CoG), ERC-2017-COG

SummaryThe emergence of mobile pastoralism in the Eurasian steppe five thousand years ago marked a unique transformation in human lifeways where, for the first time, people relied almost exclusively on herd animals of sheep, goat, cattle, and horses for sustenance and as symbols. Mobile pastoralism also generated altogether new forms of socio-political organization exceptional to the steppe that ultimately laid the foundation for nomadic states and empires. However, there remain striking gaps in our knowledge of how the pastoralist niche spread and evolved across Eurasia in the past and influenced cultural trajectories that frame the human-herd systems of today. Little is known about the scale of pastoralist movements connected with the initial translocation of domesticated animals, how mobility became embedded in pastoralist life, or how movement contributed to the formation of sophisticated political networks. There is a poor understanding of the character of herd animal husbandry strategies that were central to pastoralist subsistence and how these co-evolved alongside pastoralist dietary intake and ritual use of herd animals. We have a remarkably poor understanding of what pastoralists ate, especially the dietary contribution of dairy products - the quintessential dietary cornerstone food of pastoralist societies.
ASIAPAST addresses these gaps through a biomolecular approach that recovers the dietary and mobility histories of pastoralists and their animals recorded in bones, teeth, and pottery. This project pairs these methods to detailed analyses of the economic and symbolic use of herd animals preserved in zooarchaeological archives. These investigations draw from materials obtained from key sites that capture the transition to mobile pastoralism, its intensification, and emergence of trans-regional political structures located across the culturally connected regions of Mongolia, Kazakhstan, Russia, Kyrgyzstan, and Uzbekistan.

The emergence of mobile pastoralism in the Eurasian steppe five thousand years ago marked a unique transformation in human lifeways where, for the first time, people relied almost exclusively on herd animals of sheep, goat, cattle, and horses for sustenance and as symbols. Mobile pastoralism also generated altogether new forms of socio-political organization exceptional to the steppe that ultimately laid the foundation for nomadic states and empires. However, there remain striking gaps in our knowledge of how the pastoralist niche spread and evolved across Eurasia in the past and influenced cultural trajectories that frame the human-herd systems of today. Little is known about the scale of pastoralist movements connected with the initial translocation of domesticated animals, how mobility became embedded in pastoralist life, or how movement contributed to the formation of sophisticated political networks. There is a poor understanding of the character of herd animal husbandry strategies that were central to pastoralist subsistence and how these co-evolved alongside pastoralist dietary intake and ritual use of herd animals. We have a remarkably poor understanding of what pastoralists ate, especially the dietary contribution of dairy products - the quintessential dietary cornerstone food of pastoralist societies.
ASIAPAST addresses these gaps through a biomolecular approach that recovers the dietary and mobility histories of pastoralists and their animals recorded in bones, teeth, and pottery. This project pairs these methods to detailed analyses of the economic and symbolic use of herd animals preserved in zooarchaeological archives. These investigations draw from materials obtained from key sites that capture the transition to mobile pastoralism, its intensification, and emergence of trans-regional political structures located across the culturally connected regions of Mongolia, Kazakhstan, Russia, Kyrgyzstan, and Uzbekistan.

SummaryThe Arctic Ocean is a vast expanse of sea ice. Most of it is snow covered as are large continental regions for about half of the year. However, Global Change is arguably greatest in the Arctic, where temperatures have risen more than anywhere else in the last few decades. New record lows occurred in snow extent in June 2012 and sea ice extent in September 2012. Many observations show that widespread and sustained change is occurring in the Arctic driving this unique environmental system into a new state. This project focuses on the biogeochemical links between sea ice and snow and the composition and chemistry of the troposphere (the lowest ~10km of the atmosphere). This is an important topic because the concentrations of greenhouse gases and aerosol particles, which scatter sunlight directly and influence cloud properties, play key roles for our climate. Additionally, changes in the composition of the troposphere also affect the so-called oxidation capacity, the capability of the atmosphere to cleanse itself from pollutants.
This project aims to deliver a step change improvement in our quantitative understanding of chemical exchanges between ocean, sea ice, snow and the atmosphere in polar regions, especially the Arctic and of Arctic tropospheric chemistry. Answering these fundamental questions is essential to predict future change in the Arctic and globally. To this end a unique sea ice chamber will be constructed in the laboratory and used to quantify exchange processes in sea ice. Furthermore a hierarchy of numerical models will be used, operating at different spatial and temporal scales and degree of process description from a very detailed 1D to a global Earth System model. This will allow a breakthrough in our understanding of the importance of the changes for the composition and oxidation capacity of the atmosphere and climate and will allow us to calculate adjusted Greenhouse Warming Potentials that include these processes.

The Arctic Ocean is a vast expanse of sea ice. Most of it is snow covered as are large continental regions for about half of the year. However, Global Change is arguably greatest in the Arctic, where temperatures have risen more than anywhere else in the last few decades. New record lows occurred in snow extent in June 2012 and sea ice extent in September 2012. Many observations show that widespread and sustained change is occurring in the Arctic driving this unique environmental system into a new state. This project focuses on the biogeochemical links between sea ice and snow and the composition and chemistry of the troposphere (the lowest ~10km of the atmosphere). This is an important topic because the concentrations of greenhouse gases and aerosol particles, which scatter sunlight directly and influence cloud properties, play key roles for our climate. Additionally, changes in the composition of the troposphere also affect the so-called oxidation capacity, the capability of the atmosphere to cleanse itself from pollutants.
This project aims to deliver a step change improvement in our quantitative understanding of chemical exchanges between ocean, sea ice, snow and the atmosphere in polar regions, especially the Arctic and of Arctic tropospheric chemistry. Answering these fundamental questions is essential to predict future change in the Arctic and globally. To this end a unique sea ice chamber will be constructed in the laboratory and used to quantify exchange processes in sea ice. Furthermore a hierarchy of numerical models will be used, operating at different spatial and temporal scales and degree of process description from a very detailed 1D to a global Earth System model. This will allow a breakthrough in our understanding of the importance of the changes for the composition and oxidation capacity of the atmosphere and climate and will allow us to calculate adjusted Greenhouse Warming Potentials that include these processes.

Max ERC Funding

1 192 911 €

Duration

Start date: 2014-05-01, End date: 2016-09-30

Project acronymASICA

ProjectNew constraints on the Amazonian carbon balance from airborne observations of the stable isotopes of CO2

Researcher (PI)Wouter Peters

Host Institution (HI)WAGENINGEN UNIVERSITY

Call DetailsConsolidator Grant (CoG), PE10, ERC-2014-CoG

SummarySevere droughts in Amazonia in 2005 and 2010 caused widespread loss of carbon from the terrestrial biosphere. This loss, almost twice the annual fossil fuel CO2 emissions in the EU, suggests a large sensitivity of the Amazonian carbon balance to a predicted more intense drought regime in the next decades. This is a dangerous inference though, as there is no scientific consensus on the most basic metrics of Amazonian carbon exchange: the gross primary production (GPP) and its response to moisture deficits in the soil and atmosphere. Measuring them on scales that span the whole Amazon forest was thus far impossible, but in this project I aim to deliver the first observation-based estimate of pan-Amazonian GPP and its drought induced variations.
My program builds on two recent breakthroughs in our use of stable isotopes (13C, 17O, 18O) in atmospheric CO2: (1) Our discovery that observed δ¹³C in CO2 in the atmosphere is a quantitative measure for vegetation water-use efficiency over millions of square kilometers, integrating the drought response of individual plants. (2) The possibility to precisely measure the relative ratios of 18O/16O and 17O/16O in CO2, called Δ17O. Anomalous Δ17O values are present in air coming down from the stratosphere, but this anomaly is removed upon contact of CO2 with leaf water inside plant stomata. Hence, observed Δ17O values depend directly on the magnitude of GPP. Both δ¹³C and Δ17O measurements are scarce over the Amazon-basin, and I propose more than 7000 new measurements leveraging an established aircraft monitoring program in Brazil. Quantitative interpretation of these observations will break new ground in our use of stable isotopes to understand climate variations, and is facilitated by our renowned numerical modeling system “CarbonTracker”. My program will answer two burning question in carbon cycle science today: (a) What is the magnitude of GPP in Amazonia? And (b) How does it vary over different intensities of drought?

Severe droughts in Amazonia in 2005 and 2010 caused widespread loss of carbon from the terrestrial biosphere. This loss, almost twice the annual fossil fuel CO2 emissions in the EU, suggests a large sensitivity of the Amazonian carbon balance to a predicted more intense drought regime in the next decades. This is a dangerous inference though, as there is no scientific consensus on the most basic metrics of Amazonian carbon exchange: the gross primary production (GPP) and its response to moisture deficits in the soil and atmosphere. Measuring them on scales that span the whole Amazon forest was thus far impossible, but in this project I aim to deliver the first observation-based estimate of pan-Amazonian GPP and its drought induced variations.
My program builds on two recent breakthroughs in our use of stable isotopes (13C, 17O, 18O) in atmospheric CO2: (1) Our discovery that observed δ¹³C in CO2 in the atmosphere is a quantitative measure for vegetation water-use efficiency over millions of square kilometers, integrating the drought response of individual plants. (2) The possibility to precisely measure the relative ratios of 18O/16O and 17O/16O in CO2, called Δ17O. Anomalous Δ17O values are present in air coming down from the stratosphere, but this anomaly is removed upon contact of CO2 with leaf water inside plant stomata. Hence, observed Δ17O values depend directly on the magnitude of GPP. Both δ¹³C and Δ17O measurements are scarce over the Amazon-basin, and I propose more than 7000 new measurements leveraging an established aircraft monitoring program in Brazil. Quantitative interpretation of these observations will break new ground in our use of stable isotopes to understand climate variations, and is facilitated by our renowned numerical modeling system “CarbonTracker”. My program will answer two burning question in carbon cycle science today: (a) What is the magnitude of GPP in Amazonia? And (b) How does it vary over different intensities of drought?

Max ERC Funding

2 269 689 €

Duration

Start date: 2015-09-01, End date: 2020-08-31

Project acronymASSESS

ProjectEpisodic Mass Loss in the Most Massive Stars: Key to Understanding the Explosive Early Universe

Researcher (PI)Alceste BONANOS

Host Institution (HI)NATIONAL OBSERVATORY OF ATHENS

Call DetailsConsolidator Grant (CoG), PE9, ERC-2017-COG

SummaryMassive stars dominate their surroundings during their short lifetimes, while their explosive deaths impact the chemical evolution and spatial cohesion of their hosts. After birth, their evolution is largely dictated by their ability to remove layers of hydrogen from their envelopes. Multiple lines of evidence are pointing to violent, episodic mass-loss events being responsible for removing a large part of the massive stellar envelope, especially in low-metallicity galaxies. Episodic mass loss, however, is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We aim to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We plan to (i) derive physical parameters of a large sample of dusty, evolved targets and estimate the amount of ejected mass, (ii) constrain evolutionary models, (iii) quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to existing multi-band and time-series photometry of luminous sources in ~25 nearby galaxies. Dusty, luminous evolved massive stars will thus be automatically classified and follow-up spectroscopy will be obtained for selected targets. Atmospheric and SED modeling will yield parameters and estimates of time-dependent mass loss for ~1000 luminous stars. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.

Massive stars dominate their surroundings during their short lifetimes, while their explosive deaths impact the chemical evolution and spatial cohesion of their hosts. After birth, their evolution is largely dictated by their ability to remove layers of hydrogen from their envelopes. Multiple lines of evidence are pointing to violent, episodic mass-loss events being responsible for removing a large part of the massive stellar envelope, especially in low-metallicity galaxies. Episodic mass loss, however, is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We aim to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We plan to (i) derive physical parameters of a large sample of dusty, evolved targets and estimate the amount of ejected mass, (ii) constrain evolutionary models, (iii) quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to existing multi-band and time-series photometry of luminous sources in ~25 nearby galaxies. Dusty, luminous evolved massive stars will thus be automatically classified and follow-up spectroscopy will be obtained for selected targets. Atmospheric and SED modeling will yield parameters and estimates of time-dependent mass loss for ~1000 luminous stars. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.

Host Institution (HI)THE CHANCELLOR MASTERS AND SCHOLARS OF THE UNIVERSITY OF CAMBRIDGE

Call DetailsConsolidator Grant (CoG), PE4, ERC-2015-CoG

SummaryA technological revolution is currently taking place making it possible to noninvasively study metabolism in mammals (incl. humans) in vivo with unprecedented temporal and spatial resolution. Central to these developments is the phenomenon of hyperpolarization, which transiently enhances the magnetic resonance (MR) signals so much that real-time metabolic imaging and spectroscopy becomes possible. The first clinical translation of hyperpolarization MR technology has recently been demonstrated with prostate cancer patients.
I have played an active role in these exciting developments, through design and construction of hyperpolarization MR setups that are defining the cutting-edge for in vivo preclinical metabolic studies. However, important obstacles still exist for the technology to fulfill its enormous potential.
With this highly interdisciplinary proposal, I will overcome the principal drawbacks of current hyperpolarization technology, namely: 1) A limited time window for hyperpolarized MR detection; 2) The conventional use of potentially toxic polarizing agents; 3) The necessity to use supra-physiological doses of metabolic substrates to reach detectable MR signal
I will develop a novel hyperpolarization instrument making use of photoexcited compounds as polarizing agents to produce hyperpolarized solutions containing exclusively endogenous compounds. It will become possible to deliver hyperpolarized solutions in a quasi-continuous manner, permitting infusion of physiological doses and greatly increasing sensitivity. I will also use a complementary isotope imaging technique, the so-called CryoNanoSIMS (developed at my institution over the last year), which can image isotopic distributions in frozen tissue sections and reveal the localization of injected substrates and their metabolites with subcellular spatial resolution. Case studies will include liver and brain cancer mouse models. This work is pioneering and will create a new frontier in molecular imaging.

A technological revolution is currently taking place making it possible to noninvasively study metabolism in mammals (incl. humans) in vivo with unprecedented temporal and spatial resolution. Central to these developments is the phenomenon of hyperpolarization, which transiently enhances the magnetic resonance (MR) signals so much that real-time metabolic imaging and spectroscopy becomes possible. The first clinical translation of hyperpolarization MR technology has recently been demonstrated with prostate cancer patients.
I have played an active role in these exciting developments, through design and construction of hyperpolarization MR setups that are defining the cutting-edge for in vivo preclinical metabolic studies. However, important obstacles still exist for the technology to fulfill its enormous potential.
With this highly interdisciplinary proposal, I will overcome the principal drawbacks of current hyperpolarization technology, namely: 1) A limited time window for hyperpolarized MR detection; 2) The conventional use of potentially toxic polarizing agents; 3) The necessity to use supra-physiological doses of metabolic substrates to reach detectable MR signal
I will develop a novel hyperpolarization instrument making use of photoexcited compounds as polarizing agents to produce hyperpolarized solutions containing exclusively endogenous compounds. It will become possible to deliver hyperpolarized solutions in a quasi-continuous manner, permitting infusion of physiological doses and greatly increasing sensitivity. I will also use a complementary isotope imaging technique, the so-called CryoNanoSIMS (developed at my institution over the last year), which can image isotopic distributions in frozen tissue sections and reveal the localization of injected substrates and their metabolites with subcellular spatial resolution. Case studies will include liver and brain cancer mouse models. This work is pioneering and will create a new frontier in molecular imaging.

Max ERC Funding

2 199 146 €

Duration

Start date: 2016-09-01, End date: 2021-08-31

Project acronymAsterochronometry

ProjectGalactic archeology with high temporal resolution

Researcher (PI)Andrea MIGLIO

Host Institution (HI)THE UNIVERSITY OF BIRMINGHAM

Call DetailsConsolidator Grant (CoG), PE9, ERC-2017-COG

SummaryThe Milky Way is a complex system, with dynamical and chemical substructures, where several competing processes such as mergers, internal secular evolution, gas accretion and gas flows take place. To study in detail how such a giant spiral galaxy was formed and evolved, we need to reconstruct the sequence of its main formation events with high (~10%) temporal resolution.
Asterochronometry will determine accurate, precise ages for tens of thousands of stars in the Galaxy. We will take an approach distinguished by a number of key aspects including, developing novel star-dating methods that fully utilise the potential of individual pulsation modes, coupled with a careful appraisal of systematic uncertainties on age deriving from our limited understanding of stellar physics.
We will then capitalise on opportunities provided by the timely availability of astrometric, spectroscopic, and asteroseismic data to build and data-mine chrono-chemo-dynamical maps of regions of the Milky Way probed by the space missions CoRoT, Kepler, K2, and TESS. We will quantify, by comparison with predictions of chemodynamical models, the relative importance of various processes which play a role in shaping the Galaxy, for example mergers and dynamical processes. We will use chrono-chemical tagging to look for evidence of aggregates, and precise and accurate ages to reconstruct the early star formation history of the Milky Way’s main constituents.
The Asterochronometry project will also provide stringent observational tests of stellar structure and answer some of the long-standing open questions in stellar modelling (e.g. efficiency of transport processes, mass loss on the giant branch, the occurrence of products of coalescence / mass exchange). These tests will improve our ability to determine stellar ages and chemical yields, with wide impact e.g. on the characterisation and ensemble studies of exoplanets, on evolutionary population synthesis, integrated colours and thus ages of galaxies.

The Milky Way is a complex system, with dynamical and chemical substructures, where several competing processes such as mergers, internal secular evolution, gas accretion and gas flows take place. To study in detail how such a giant spiral galaxy was formed and evolved, we need to reconstruct the sequence of its main formation events with high (~10%) temporal resolution.
Asterochronometry will determine accurate, precise ages for tens of thousands of stars in the Galaxy. We will take an approach distinguished by a number of key aspects including, developing novel star-dating methods that fully utilise the potential of individual pulsation modes, coupled with a careful appraisal of systematic uncertainties on age deriving from our limited understanding of stellar physics.
We will then capitalise on opportunities provided by the timely availability of astrometric, spectroscopic, and asteroseismic data to build and data-mine chrono-chemo-dynamical maps of regions of the Milky Way probed by the space missions CoRoT, Kepler, K2, and TESS. We will quantify, by comparison with predictions of chemodynamical models, the relative importance of various processes which play a role in shaping the Galaxy, for example mergers and dynamical processes. We will use chrono-chemical tagging to look for evidence of aggregates, and precise and accurate ages to reconstruct the early star formation history of the Milky Way’s main constituents.
The Asterochronometry project will also provide stringent observational tests of stellar structure and answer some of the long-standing open questions in stellar modelling (e.g. efficiency of transport processes, mass loss on the giant branch, the occurrence of products of coalescence / mass exchange). These tests will improve our ability to determine stellar ages and chemical yields, with wide impact e.g. on the characterisation and ensemble studies of exoplanets, on evolutionary population synthesis, integrated colours and thus ages of galaxies.

SummaryBrain information processing is commonly thought to be a neuronal performance. However recent data point to a key role of astrocytes in brain development, activity and pathology. Indeed astrocytes are now viewed as crucial elements of the brain circuitry that control synapse formation, maturation, activity and elimination. How do astrocytes exert such control is matter of intense research, as they are now known to participate in critical developmental periods as well as in psychiatric disorders involving synapse alterations. Thus unraveling how astrocytes control synaptic circuit formation and maturation is crucial, not only for our understanding of brain development, but also for identifying novel therapeutic targets.
We recently found that connexin 30 (Cx30), an astroglial gap junction subunit expressed postnatally, tunes synaptic activity via an unprecedented non-channel function setting the proximity of glial processes to synaptic clefts, essential for synaptic glutamate clearance efficacy. Our work not only reveals Cx30 as a key determinant of glial synapse coverage, but also extends the classical model of neuroglial interactions in which astrocytes are generally considered as extrasynaptic elements indirectly regulating neurotransmission. Yet the molecular mechanisms involved in such control, its dynamic regulation by activity and impact in a native developmental context are unknown. We will now address these important questions, focusing on the involvement of this novel astroglial function in wiring developing synaptic circuits.
Thus using a multidisciplinary approach we will investigate:
1) the molecular and cellular mechanisms underlying Cx30 regulation of synaptic function
2) the activity-dependent dynamics of Cx30 function at synapses
3) a role for Cx30 in wiring synaptic circuits during critical developmental periods
This ambitious project will provide essential knowledge on the molecular mechanisms underlying astroglial control of synaptic circuits.

Brain information processing is commonly thought to be a neuronal performance. However recent data point to a key role of astrocytes in brain development, activity and pathology. Indeed astrocytes are now viewed as crucial elements of the brain circuitry that control synapse formation, maturation, activity and elimination. How do astrocytes exert such control is matter of intense research, as they are now known to participate in critical developmental periods as well as in psychiatric disorders involving synapse alterations. Thus unraveling how astrocytes control synaptic circuit formation and maturation is crucial, not only for our understanding of brain development, but also for identifying novel therapeutic targets.
We recently found that connexin 30 (Cx30), an astroglial gap junction subunit expressed postnatally, tunes synaptic activity via an unprecedented non-channel function setting the proximity of glial processes to synaptic clefts, essential for synaptic glutamate clearance efficacy. Our work not only reveals Cx30 as a key determinant of glial synapse coverage, but also extends the classical model of neuroglial interactions in which astrocytes are generally considered as extrasynaptic elements indirectly regulating neurotransmission. Yet the molecular mechanisms involved in such control, its dynamic regulation by activity and impact in a native developmental context are unknown. We will now address these important questions, focusing on the involvement of this novel astroglial function in wiring developing synaptic circuits.
Thus using a multidisciplinary approach we will investigate:
1) the molecular and cellular mechanisms underlying Cx30 regulation of synaptic function
2) the activity-dependent dynamics of Cx30 function at synapses
3) a role for Cx30 in wiring synaptic circuits during critical developmental periods
This ambitious project will provide essential knowledge on the molecular mechanisms underlying astroglial control of synaptic circuits.

SummaryThe main goal of ASTRUm is to employ stored and cooled radioactive ions for forefront nuclear astrophysics research. Four key experiments are proposed to be conducted at GSI in Darmstadt, which holds the only facility to date capable of storing highly charged radionuclides in the required element and energy range. The proposed experiments can hardly be conducted by any other technique or method.
The weak decay matrix element for the transition between the 2.3 keV state in 205Pb and the ground state of 205Tl will be measured via the bound state beta decay measurement of fully ionized 205Tl81+. This will provide the required data to determine the solar pp-neutrino flux integrated over the last 5 million years and will allow us to unveil the astrophysical conditions prior to the formation of the solar system.
The measurements of the alpha-decay width of the 4.033 MeV excited state in 19Ne will allow us to constrain the conditions for the ignition of the rp-process in X-ray bursters.
ASTRUm will open a new field by enabling for the first time measurements of proton- and alpha-capture reaction cross-sections on radioactive nuclei of interest for the p-process of nucleosynthesis.
Last but not least, broad band mass and half-life measurements in a ring is the only technique to precisely determine these key nuclear properties for nuclei with half-lives as short as a millisecond and production rates of below one ion per day.
To accomplish these measurements with highest efficiency, sensitivity and precision, improved detector systems will be developed within ASTRUm. Possible applications of these systems go beyond ASTRUm objectives and will be used in particular in accelerator physics.
The instrumentation and experience gained within ASTRUm will be indispensable for planning the future, next generation storage ring projects, which are launched or proposed at several radioactive ion beam facilities.

The main goal of ASTRUm is to employ stored and cooled radioactive ions for forefront nuclear astrophysics research. Four key experiments are proposed to be conducted at GSI in Darmstadt, which holds the only facility to date capable of storing highly charged radionuclides in the required element and energy range. The proposed experiments can hardly be conducted by any other technique or method.
The weak decay matrix element for the transition between the 2.3 keV state in 205Pb and the ground state of 205Tl will be measured via the bound state beta decay measurement of fully ionized 205Tl81+. This will provide the required data to determine the solar pp-neutrino flux integrated over the last 5 million years and will allow us to unveil the astrophysical conditions prior to the formation of the solar system.
The measurements of the alpha-decay width of the 4.033 MeV excited state in 19Ne will allow us to constrain the conditions for the ignition of the rp-process in X-ray bursters.
ASTRUm will open a new field by enabling for the first time measurements of proton- and alpha-capture reaction cross-sections on radioactive nuclei of interest for the p-process of nucleosynthesis.
Last but not least, broad band mass and half-life measurements in a ring is the only technique to precisely determine these key nuclear properties for nuclei with half-lives as short as a millisecond and production rates of below one ion per day.
To accomplish these measurements with highest efficiency, sensitivity and precision, improved detector systems will be developed within ASTRUm. Possible applications of these systems go beyond ASTRUm objectives and will be used in particular in accelerator physics.
The instrumentation and experience gained within ASTRUm will be indispensable for planning the future, next generation storage ring projects, which are launched or proposed at several radioactive ion beam facilities.

Max ERC Funding

1 874 750 €

Duration

Start date: 2016-04-01, End date: 2021-03-31

Project acronymATTOLIQ

ProjectAttosecond X-ray spectroscopy of liquids

Researcher (PI)Hans Jakob WÖRNER

Host Institution (HI)EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH

Call DetailsConsolidator Grant (CoG), PE4, ERC-2017-COG

SummaryCharge and energy transfer are the key steps underlying most chemical reactions and biological transformations. The purely electronic dynamics that control such processes take place on attosecond time scales. A complete understanding of these dynamics on the electronic level therefore calls for new experimental methods with attosecond resolution that are applicable to aqueous environments. We propose to combine the element sensitivity of X-ray spectroscopy with attosecond temporal resolution and ultrathin liquid microjets to study electronic dynamics of relevance to chemical, biological and photovoltaic processes. We will build on our recent achievements in demonstrating femtosecond time-resolved measurements in the water, attosecond pho-toelectron spectroscopy on a liquid microjet and measuring and controlling attosecond charge migration in isolated molecules. We will first concentrate on liquid water to study its electronic dynamics following outer-valence ionization, the formation pathway of the solvated electron and the time scales and intermolecular Coulombic decay following inner-valence or core-level ionization. Second, we will turn to solvated species and measure electronic dynamics and charge migration in solvated molecules, transition-metal complexes and pho-toexcited nanoparticles. These goals will be achieved by developing several innovative experimental tech-niques. We will develop a source of isolated attosecond pulses covering the water window (285-538 eV) and combine it with a flat liquid microjet to realize attosecond transient absorption in liquids. We will complement these measurements with attosecond X-ray emission spectroscopy, Auger spectroscopy and a novel hetero-dyne-detected variant of resonant inelastic Raman scattering, exploiting the large bandwidth that is naturally available from attosecond X-ray sources.

Charge and energy transfer are the key steps underlying most chemical reactions and biological transformations. The purely electronic dynamics that control such processes take place on attosecond time scales. A complete understanding of these dynamics on the electronic level therefore calls for new experimental methods with attosecond resolution that are applicable to aqueous environments. We propose to combine the element sensitivity of X-ray spectroscopy with attosecond temporal resolution and ultrathin liquid microjets to study electronic dynamics of relevance to chemical, biological and photovoltaic processes. We will build on our recent achievements in demonstrating femtosecond time-resolved measurements in the water, attosecond pho-toelectron spectroscopy on a liquid microjet and measuring and controlling attosecond charge migration in isolated molecules. We will first concentrate on liquid water to study its electronic dynamics following outer-valence ionization, the formation pathway of the solvated electron and the time scales and intermolecular Coulombic decay following inner-valence or core-level ionization. Second, we will turn to solvated species and measure electronic dynamics and charge migration in solvated molecules, transition-metal complexes and pho-toexcited nanoparticles. These goals will be achieved by developing several innovative experimental tech-niques. We will develop a source of isolated attosecond pulses covering the water window (285-538 eV) and combine it with a flat liquid microjet to realize attosecond transient absorption in liquids. We will complement these measurements with attosecond X-ray emission spectroscopy, Auger spectroscopy and a novel hetero-dyne-detected variant of resonant inelastic Raman scattering, exploiting the large bandwidth that is naturally available from attosecond X-ray sources.

SummaryTectonic phenomena at the Earth's surface, like volcanic eruptions and earthquakes,are driven by convection deep in the mantle. Seismic tomography has been very successful in elucidating the Earth's internal velocity structure. However, seismic velocity is insufficient to obtain robust estimates of temperature and composition, and make direct links with mantle convection. Thus, fundamental questions remain unanswered: Do subducting slabs bring water into the lower mantle? Are the large low-shear velocity provinces under the Pacific and Africa mainly thermal or compositional? Is there any partial melt or water near the mantle transition zone or core mantle boundary?
Seismic attenuation, or loss of energy, is key to mapping melt, water and temperature variations, and answering these questions. Unfortunately, attenuation has only been imaged using short- and intermediate-period seismic data, showing little similarity even for the upper mantle and no reliable lower mantle models exist. The aim of ATUNE is to develop novel full-spectrum techniques and apply them to Earth's long period free oscillations to observe global-scale regional variations in seismic attenuation from the lithosphere to the core mantle boundary. Scattering and focussing - problematic for shorter period techniques - are easily included using cross-coupling (or resonance) between free oscillations not requiring approximations. The recent occurrence of large earthquakes, increase in computer power and my world-leading expertise in free oscillations now make it possible to increase the frequency dependence of attenuation to a much wider frequency band, allowing us to distinguish between scattering (redistribution of energy) versus intrinsic attenuation. ATUNE will deliver the first ever full-waveform global tomographic model of 3D attenuation variations in the lower mantle, providing essential constraints on melt, water and temperature for understanding the complex dynamics of our planet.

Tectonic phenomena at the Earth's surface, like volcanic eruptions and earthquakes,are driven by convection deep in the mantle. Seismic tomography has been very successful in elucidating the Earth's internal velocity structure. However, seismic velocity is insufficient to obtain robust estimates of temperature and composition, and make direct links with mantle convection. Thus, fundamental questions remain unanswered: Do subducting slabs bring water into the lower mantle? Are the large low-shear velocity provinces under the Pacific and Africa mainly thermal or compositional? Is there any partial melt or water near the mantle transition zone or core mantle boundary?
Seismic attenuation, or loss of energy, is key to mapping melt, water and temperature variations, and answering these questions. Unfortunately, attenuation has only been imaged using short- and intermediate-period seismic data, showing little similarity even for the upper mantle and no reliable lower mantle models exist. The aim of ATUNE is to develop novel full-spectrum techniques and apply them to Earth's long period free oscillations to observe global-scale regional variations in seismic attenuation from the lithosphere to the core mantle boundary. Scattering and focussing - problematic for shorter period techniques - are easily included using cross-coupling (or resonance) between free oscillations not requiring approximations. The recent occurrence of large earthquakes, increase in computer power and my world-leading expertise in free oscillations now make it possible to increase the frequency dependence of attenuation to a much wider frequency band, allowing us to distinguish between scattering (redistribution of energy) versus intrinsic attenuation. ATUNE will deliver the first ever full-waveform global tomographic model of 3D attenuation variations in the lower mantle, providing essential constraints on melt, water and temperature for understanding the complex dynamics of our planet.